I have a quite densely planted 4 ft tank with driftwood, and I have just discovered that 3 of my clown loaches have ich. I find it virtually impossible to catch them to transfer to a quarantine tank. Is there any way I can treat the fish in the main tank without affecting the look of the tank, ie. water turning green color due to the medication, etc? What can I use for treating ich without affecting my plants? Thanks. Tony